type statetype
    tool as long
    fcolor as long
    bcolor as long
    offsetX as long
    offsetY as long
    zoom as single
    brushsize as integer
    startX as integer
    startY as integer
    isDrawing as integer
end type

type layertype
    ihandle as long
    blendmode as long
    filter as long
    kind as long
end type

redim shared layers(3) as layertype
dim shared state as statetype

dim shared showtoolbox as _byte: showtoolbox=-1
dim shared showcolorpicker as _byte: showcolorpicker=-1

dim shared mouseclicked as integer
dim shared mousedown as integer
dim shared rmouseclicked as integer
dim shared rmousedown as integer

$resize:on
screen _newimage(750,480,32)
_delay 0.1
temp&=_resize
redim shared pal(0) as _unsigned long
dim as integer ch1,ch2,ch3,bt
loadpalette "slso8",pal()
layers(0).ihandle=_newimage(320,320,32)
layers(1).ihandle=_newimage(320,320,32)
layers(2).ihandle=_newimage(320,320,32)
layers(3).ihandle=_newimage(320,320,32)

_dest layers(0).ihandle
line (0,0)-(_width-1,_height-1),_rgb32(255),bf
_dest 0
state.tool = 1
state.fcolor = 1
state.bcolor = 2
state.zoom = 1.0
state.offsetX = 70 + 20 ' To the right of the toolbox
state.offsetY = 20
state. brushsize = 1
dim lastMX, lastMY
dim diffX as integer
dim diffY as integer
dim oldWidth as integer
dim oldHeight as integer
dim keyin as string

oldWidth=_width
oldHeight=_height
do
    if CheckResize(_source) = -1 THEN
        diffX = _width - oldWidth
        diffY = _height - oldHeight
        state.offsetX = state.offsetX + (diffX / 2)
        state.offsetY = state.offsetY + (diffY / 2)
        oldWidth = _width
        oldHeight = _height
    end if

    line (0,0)-(_width-1,_height-1),backgroundcolor1,bf

    'Mouse Handling
    while _mouseinput:mw=mw+_mousewheel:wend
    mouseclicked = 0
    rmouseclicked = 0
    if mousedown = -1 and _mousebutton(1) = 0 then mouseclicked = -1
    if rmousedown = -1 and _mousebutton(2) = 0 then rmouseclicked = -1
    mousedown = _mousebutton(1)
    rmousedown = _mousebutton(2)

    ' Panning (Middle Mouse)
    if _mousebutton(3) then
        state.offsetX = int(state.offsetX + (_mousex - lastMX))
        state.offsetY = int(state.offsetY + (_mousey - lastMY))
    end if
    lastMX = _mousex: lastMY = _mousey

    ' Zooming
        if mw <> 0 then
            ' 1. Capture current world position
            dim mouseWorldX as single: mouseWorldX = (_mousex - state.offsetX) / state.zoom
            dim mouseWorldY as single: mouseWorldY = (_mousey - state.offsetY) / state.zoom

            ' 2. Calculate the new zoom level (Snap to whole numbers)
            if mw > 0 then
                state.zoom = state.zoom + 1
            else
                state.zoom = state.zoom - 1
            end if

            ' 3. Constrain zoom (Min 1, Max 20)
            if state.zoom < 1 then state.zoom = 1
            if state.zoom > 20 then state.zoom = 20

            ' 4. Adjust offsets and LOCK them to integers
            ' This prevents the canvas from sitting "between" screen pixels
            state.offsetX = _mousex - (mouseWorldX * state.zoom)
            state.offsetY = _mousey - (mouseWorldY * state.zoom)

            mw = 0
        end if

    ' Keyboarding
    keyin=inkey$
    select case keyin
    case "+"
        state.brushsize=state.brushsize+1
    case "-"
        if state.brushsize>1 then state.brushsize=state.brushsize-1
    case chr$(19) ' ctrl+s
        'TODO: save logic
    case chr$(27)' esc
        menu
    case "h"
        state.zoom = 1.0
        state.offsetX = (_width / 2) - (_width(layers(0).ihandle) / 2)
        state.offsetY = (_height / 2) - (_height(layers(0).ihandle) / 2)
    case "t"
        showtoolbox=not showtoolbox
    case "c"
        showcolorpicker=not showcolorpicker
    end select

    canvas
    if showtoolbox then toolbox
    if showcolorpicker then colorpicker

    _limit 30
    _display
loop

sub toolbox
    dim i, x, y
    dim btnSize : btnSize = 32
    dim spacing : spacing = 1

    for i = 0 to 19
        ' Force integer math to keep columns locked at 2
        ' x will only ever be 0 or 33
        x = (i mod 2) * (btnSize + spacing)

        ' y will only increase every 2 buttons
        ' Use Int() if your language doesn't support the \ operator
        y = Int(i / 2) * (btnSize + spacing)

        if imagebutton(x, y, btnSize, btnSize, icon(i)) then
            state.tool = i + 1
        end if
    next
end sub

sub colorpicker
    dim img as long
    img=_newimage(16,16,32)
    for i=0 to ubound(pal)
        _dest img
        cls ,pal(i)
        line (0,0)-(_width-1,height-1),pal(i),bf
        _dest 0
        select case imagebutton(i*16,_height-17,16,16,img)
            case -1
                state.fcolor=pal(i)
            case -2
                state.bcolor=pal(i)
        end select
    next i
    _freeimage img
end sub

sub canvas

    ' 1. Define the Viewport (The "Window" on your screen)
    dim viewX1 as integer
    if showtoolbox then viewX1 = 70 else viewX1 = 0
    dim viewY1 as integer: viewY1 = 0
    dim viewX2 as integer: viewX2 = _width - 1
    dim viewY2 as integer
    if showcolorpicker then viewY2 = _height - 20 else viewY2 = _height - 1

    _dest 0

    ' 2. Render Layers with Clipping
    dim srcX1 as long
    dim srcY1 as long
    dim srcX2 as long
    dim srcY2 as long
    dim drawX1 as long
    dim drawY1 as long
    dim drawX2 as long
    dim drawY2 as long

    dim i as integer
    for i = 0 to ubound(layers)
        dim img as long: img = layers(i).ihandle
        dim imgW as integer: imgW = _width(img)
        dim imgH as integer: imgH = _height(img)

        ' Current scaled dimensions
        dim fullScaledW as single: fullScaledW = imgW * state.zoom
        dim fullScaledH as single: fullScaledH = imgH * state.zoom

        ' Calculate visible area in screen coordinates (Overlap of image and viewport)
         drawX1 = state.offsetX
         drawY1 = state.offsetY
         drawX2 = state.offsetX + fullScaledW
         drawY2 = state.offsetY + fullScaledH

        ' Clip the destination to the Viewport
        if drawX1 < viewX1 then drawX1 = viewX1
        if drawY1 < viewY1 then drawY1 = viewY1
        if drawX2 > viewX2 then drawX2 = viewX2
        if drawY2 > viewY2 then drawY2 = viewY2

        ' Only draw if the image is actually inside the viewport
        if drawX2 > drawX1 and drawY2 > drawY1 then
            ' Map screen-clipped coordinates back to the source image coordinates
             srcX1 = int((drawX1 - state.offsetX) / state.zoom)
             srcY1 = int((drawY1 - state.offsetY) / state.zoom)
             srcX2 = int((drawX2 - state.offsetX) / state.zoom)
             srcY2 = int((drawY2 - state.offsetY) / state.zoom)

            ' Syntax: _PUTIMAGE (destX1, destY1)-(destX2, destY2), sourceHandle, 0, (srcX1, srcY1)-(srcX2, srcY2)
            _putimage (drawX1, drawY1)-(drawX2, drawY2), img, 0, (srcX1, srcY1)-(srcX2, srcY2)
        end if
    next

    ' 2.5 if the mouse is in ui thats all we need
     if showtoolbox then
        if _mousex >= 0 and _mousex <= 70 then
            exit sub
        end if
    end if
    if showcolorpicker then
        if _mousey >= _height - 20 then
            exit sub
        end if
    end if

    ' 3. Calculate Canvas Coordinates
    dim canX as integer: canX = int((_mousex - state.offsetX) / state.zoom)
    dim canY as integer: canY = int((_mousey - state.offsetY) / state.zoom)


    static polypoints(200) as single
    static pointCount as integer

    static drawCol
    if _mousebutton(1) then drawCol = state.fcolor
    if _mousebutton(2) then drawCol = state.bcolor

    ' 4. Interaction Logic
    'if _mousex > boxX1 then
        ' Start Drawing Logic
        if state.tool = 9 and (mouseclicked or rmouseclicked) then
            _dest layers(1).ihandle
            _source layers(1).ihandle
            if mouseclicked then
                floodfill canX,canY,state.fcolor
            else
                floodfill canX,canY,state.bcolor
            end if
            _dest 0
            _source 0
            exit sub
        end if

        if state.tool = 10 and (mouseclicked or rmouseclicked) then
            _dest layers(1).ihandle
            _source layers(1).ihandle
            if mouseclicked then
                state.fcolor=point(canX,canY)
            else
                state.bcolor=point(canX,canY)
            end if
            _dest 0
            _source 0
            exit sub
        end if

        if state.tool = 7 or state.tool = 8 then
            if mouseclicked then
                polypoints(pointCount * 2) = canX
                polypoints(pointCount * 2 + 1) = canY
                pointCount = pointCount + 1
                state.isDrawing = -1
            end if
        else
            if (mousedown or rmousedown) and state.isDrawing = 0 then
                state.startX = canX
                state.startY = canY
                state.isDrawing = -1
            end if
        end if

        if state.isDrawing then
            ' We use Layer 2 as the temporary preview "rubber-band" layer
            _dest layers(2).ihandle
            cls , 0

            select case state.tool
                case 1 ' Pencil
                    _dest layers(1).ihandle
                    thickline state.startX, state.startY, canX, canY, drawCol
                    state.startX = canX: state.startY = canY
                case 2 ' Straight Line
                    thickline state.startX, state.startY, canX, canY, drawCol
                case 3 ' Circle
                    dim r as single: r = sqr((canX - state.startX)^2 + (canY - state.startY)^2)
                    thickcircle state.startX, state.startY, r + 1, drawCol
                case 4 ' Filled Circle
                    dim r_f as single: r_f = sqr((canX - state.startX)^2 + (canY - state.startY)^2)
                    filledcircle state.startX, state.startY, r_f, drawCol
                case 5 ' Rect
                    thickline state.startX, state.startY, canX, state.startY, drawCol
                    thickline canX, state.startY, canX, canY, drawCol
                    thickline canX, canY, state.startX, canY, drawCol
                    thickline state.startX, canY, state.startX, state.startY, drawCol
                case 6 ' Filled Rect
                    line (state.startX, state.startY)-(canX, canY), drawCol, bf
                case 7, 8 ' Polygons
                    if pointCount > 0 then
                        for p = 1 to pointCount - 1
                            thickline polypoints((p - 1) * 2), polypoints((p - 1) * 2 + 1), polypoints(p * 2), polypoints(p * 2 + 1), state.fcolor
                        next p
                        thickline polypoints((pointCount - 1) * 2), polypoints((pointCount - 1) * 2 + 1), canX, canY, state.fcolor
                    end if
            end select

            ' 5. Commit Logic
            dim commit as integer: commit = 0
            if state.tool = 7 or state.tool = 8 then
                if rmouseclicked then commit = -1
            else
                if (mousedown=0) and (rmousedown=0) then commit = -1
            end if

            if commit then
                _dest layers(1).ihandle ' Final destination is always the drawing layer
                if (state.tool = 8 or state.tool=7) and pointCount > 2 then
                    redim finalP(pointCount * 2 - 1) as long
                    for p = 0 to (pointCount * 2) - 1: finalP(p) = polypoints(p): next
                    if state.tool =8 then filledPolygon finalP(), state.fcolor else Polygon finalP(), state.fcolor
                else
                    ' Merge the preview into the drawing layer
                    _putimage , layers(2).ihandle, layers(1).ihandle
                end if

                _dest layers(2).ihandle: cls , 0
                state.isDrawing = 0
                pointCount = 0
            end if
        end if
    'end if
    _dest 0 ' Ensure we return to main screen
end sub

function icon (index as long)
    static init as integer
    static icons() as long
    if not init then
        redim icons(19) as long ' Room for 20 icons

        ' Define your specific tool icons here
        icons(0) = _newimage(32,32,32): _dest icons(0): line (5, 27)-(27, 5): _dest 0
        icons(1) = _newimage(32,32,32): _dest icons(1): circle (15, 15), 13: _dest 0
        icons(2) = _newimage(32,32,32): _dest icons(2): line (5, 5)-(27, 27), , b: _dest 0
        icons(6) = _newimage(32,32,32): _dest icons(6)
        line (5,15)-(15,5):line -(25,15):line -(20,25): line -(10,25):line -(5,15)
        _dest 0

        icons(7) = _newimage(32, 32, 32): _dest icons(7)
        ' Draw a small filled shape for the filled polygon icon
        for fy = 10 to 20: line (10, fy)-(22, fy): next
        _dest 0
        icons(8) = _newimage(32, 32, 32): _dest icons(8)
        ' Simple "Bucket" icon
        line (8, 10)-(24, 10): line -(26, 22): line -(6, 22): line -(8, 10)
        line (10, 8)-(22, 8) ' Handle
        _dest 0
        ' Fill the remaining slots with blank 32x32 images
        dim j as integer
        for j = 0 to 19
            if icons(j) = 0 then icons(j) = _newimage(32, 32, 32)
        next

        init = -1
    end if

    ' Bounds checking to prevent returning 0 or crashing
    if index >= 0 and index <= 19 then
        icon = icons(index)
    else
        icon = icons(0)
    end if
end function

'$include: 'include/ui.bm'
'$include: 'include/imgout.bm'
'$include: 'include/palette.bm'
'$include: 'include/tools.bm'
''$include: 'include/effects.bm'

function adduiicon(imagehandle as long)
    dim unknown as long
    adduiicon=__internaluiicon(unknown,imagehandle,1)
end function

function adduiiconfromfile(filename as string)
    dim unknown as long
    adduiiconfromfile=__internaluiicon(unknown,_loadimage(filename),1)
end function

function uiicon(index)
    dim unknown as long
    uiicon=internaluiicon(index,unknown,2)
end function

function __internaluiicon&(index as long,imagehandle as long,mode as integer)
    static init as integer
    static icons() as long
    if not init or mode=3 then
        if mode<3 then
            redim icons(3) as long
        else
            _freeimage icons(0)
            _freeimage icons(1)
            _freeimage icons(2)
            _freeimage icons(3)
        end if
        icons(0)=_newimage(23,23,32) 'Up arrow'
        _dest icons(0)
        color textcolor

        icons(1)=_newimage(23,23,32) 'Down arrow'
        _dest icons(1)
        color textcolor

        icons(2)=_newimage(23,23,32) 'Left arrow'
        _dest icons(2)
        color textcolor

        icons(3)=_newimage(23,23,32) 'Right arrow'
        _dest icons(3)
        color textcolor

        _dest 0
        init=-1
    end if

    select case mode
        case 1
            redim _preserve icons(ubound(icons)+1)
            icons(ubound(icons))=imagehandle
            __internaluiicon=ubound(icons)
        case 2
            __internaluiicon=icons(index)
    end select
end function


FUNCTION CheckResize (CurrentScreen AS _UNSIGNED LONG) 'pulled straight out of the wiki'
    DIM TempScreen AS _UNSIGNED LONG
    CheckResize = 0
    IF _RESIZE THEN
        TempScreen = _COPYIMAGE(CurrentScreen, 32)
        SCREEN TempScreen
        _FREEIMAGE CurrentScreen
        CurrentScreen = _NEWIMAGE(_RESIZEWIDTH, _RESIZEHEIGHT, 32)
        SCREEN CurrentScreen
        _PUTIMAGE (0, 0), TempScreen, CurrentScreen
        _DISPLAY
        _FREEIMAGE TempScreen
        CheckResize = -1
    END IF

END FUNCTION


sub menu()
Line (0,0)-(_width-1,_height-1),_rgb32(0,1),bf
do until done
k$=inkey$
while _mouseinput:wend
mouseclicked=mbd and not _mousebutton(1)
mbd=_mousebutton(1)
if button(10,10,60,23,"open") then system
if button(10,34,60,23,"save") then system
if button(10,56,60,23,"exit") then system

if k$=chr$(27) then done=-1
_limit 30
_display
loop
end sub